The Sixty-Year Climate Cycle

[last update:
2012/10/10]

Cycles are apparent in climate data. This document examines
the appearance of the approximately 60-year cycle that shows up in many
areas. This cycle length is not exactly 60 years and varies by a few years
between various climatic phenomena and locations.

The following shows the Climatic Research Unit global average
temperature anomalies (the IPCC uses data provided by HadCRU
– plot from: [http://hadobs.metoffice.com/hadcrut3/diagnostics/global/nh+sh/]).
Two cycles have been highlighted in rectangles (not peak-to-peak). The final
part of the figure shows the cycle from the second rectangle, changed to red
and superimposed on the first cycle (vertically shifted by 0.3 degrees).

As can be seen from the above
figures, the two cycles were nearly identical, and yet the IPCC says the
models can explain the early 1900s cycle with only natural forcings, but anthropogenic CO2 is needed for the later
cycle. There appears to be a serious problem with the models when two
identical cycles have two very different causes.

The cycle length is approximately 62 years, with maxima
around 1879, 1942 and 2002, and minima around 1910 and 1972.

When the claim is made that the
Earth has warmed 0.74 degrees from 1906 – 2005 (IPCC AR4 [http://www.ipcc.ch/pdf/assessment-report/ar4/syr/ar4_syr_spm.pdf]),
they are spuriously ignoring the 60-year cycle and arbitrarily choosing a
start and end for a linear trend within a non-linear cycle. The red line on
the figure below shows the 0.74 degrees per century. The linear warming trend
shown when accounting for the cycle is actually about 0.4 degrees per century
as shown by the blue line on the figure below.

The IPCC
also claims in the same AR4 summary document that “The linear warming trend over the last 50 years
(0.13 [0.10 to 0.16]°C per decade) is nearly twice
that for the last 100 years.” This is shown by the green line on the
figure above. They call this “acceleration” of the warming trend, completely
ignoring that a linear trend cannot be calculated arbitrarily in cyclical
data.

The IPCC is either stupid, or trying to deceive by
obfuscating the statistics (the latter is more likely).

Zhen-Shan and Xian (“Multi-scale analysis of global
temperature changes and trend of a drop in temperature in the next 20 years”,
Meteorology and Atmospheric Physics, Vol.95, 2007 [http://www.springerlink.com/content/g28u12g2617j5021/]):
“A novel multi-timescale
analysis method, Empirical Mode Decomposition (EMD), is used to diagnose the
variation of the annual mean temperature data of the global, Northern
Hemisphere (NH) and China from 1881 to 2002. The results show that: (1)
Temperature can be completely decomposed into four timescales quasi-periodic
oscillations including an ENSO-like mode, a 6–8-year signal, a 20-year signal
and a 60-year signal, as well as a trend. With each contributing ration of
the quasi-periodicity discussed, the trend and the 60-year timescale
oscillation of temperature variation are the most prominent.”

The cycle length is approximately 62 years with maxima
around 1878, 1943 and 2004, and minima around 1912 and 1974.

The AMO cycle is very close to the global temperature
cycle in terms of cycle length and occurrence of maxima / minima.

Knudsen et al (“Tracking the Atlantic Multidecadal Oscillation through the last 8,000 years”,
Nature Communications, 2011, [http://www.nature.com/ncomms/journal/v2/n2/full/ncomms1186.html]):
“The nature and origin of
the AMO is uncertain, and it remains unknown whether it represents a
persistent periodic driver in the climate system, or merely a transient
feature. Here, we show that distinct, ~55- to 70-year oscillations
characterized the North Atlantic ocean-atmosphere variability over the past
8,000 years. We test and reject the hypothesis that this climate
oscillation was directly forced by periodic changes in solar activity. We
therefore conjecture that a quasi-persistent ~55- to 70-year AMO, linked to
internal ocean-atmosphere variability, existed during large parts of the
Holocene. Our analyses further suggest that the coupling from the AMO to
regional climate conditions was modulated by orbitally
induced shifts in large-scale ocean-atmosphere circulation.”

A 2012 paper (Chambers et al, “Is
there a 60-year oscillation in global mean sea level?”,
Geophysical Research Letters Vol 39 [http://www.agu.org/pubs/crossref/2012/2012GL052885.shtml]
) states: “We examine long tide gauge records in every ocean basin to
examine whether a quasi 60-year oscillation
observed in global mean sea level (GMSL) reconstructions reflects a true
global oscillation, or an artifact associated with a small number of gauges.
We find that there is a significant
oscillation with a period around 60-years in the majority of the tide gauges
examined during the 20th Century, and that it appears in every ocean basin.
Averaging of tide gauges over regions shows that the phase and amplitude of
the fluctuations are similar in the North Atlantic, western North Pacific, and
Indian Oceans, while the signal is shifted by 10 years in the western
South Pacific. The only sampled region with no apparent 60-year fluctuation
is the Central/Eastern North Pacific. The phase of the 60-year oscillation
found in the tide gauge records is such that sea level in the North Atlantic,
western North Pacific, Indian Ocean, and western South Pacific has been
increasing since 1985–1990. Although the tide gauge data are still too
limited, both in time and space, to determine conclusively that there is a
60-year oscillation in GMSL, the possibility should be considered when
attempting to interpret the acceleration in the rate of global and regional
mean sea level rise.”

The following figure from that paper shows the
approximately 60-year cycle in the sea level data.

Southwest US Drought Cycle

The following figure shows the southwest United States
drought index 1900 - 2002

The cycle length is approximately 64 years, with maxima
(wet) around 1918 and 1982 and a minimum (drought) in 1955.

The southwest US PHDI has about a 5 year lag from the AMO.

Length of Day / Atmospheric Circulation Index

A UN Food and Agricultural Organization (FAO) report on “Climate
Change and Long-Term Fluctuation of Commercial Catches”, 2001 [ftp://ftp.fao.org/docrep/fao/005/y2787e/y2787e01.pdf]
provides the following figures showing length of day (LOD) inverted (left)
and the Zonal Atmospheric Circulation Index (right). Both exhibit an
approximately 60-year cycle.

The FAO
report stated: “Spectral
analysis of the time series of dT, ACI and Length
Of Day (LOD) estimated from direct observations (110-150 years) showed a
clear 55-65 year periodicity. Spectral analysis of the reconstructed time
series of the air surface temperatures for the last 1500 years suggested the
similar (55-60 year) periodicity. Analysis of 1600 years long
reconstructed time series of sardine and anchovy biomass in Californian
upwelling also revealed a regular 50-70 years fluctuation. Spectral analysis
of the catch statistics of main commercial species for the last 50-100 years
also showed cyclical fluctuations of about 55-years.” The following
figures are from that report and are also viewable at: [http://www.fao.org/docrep/005/Y2787E/y2787e03a.htm]

The FAO report states the LOD is “a geophysical index that characterizes variation
in the earth rotational velocity … Spectral density analysis of the LOD time
series for 1850-1998 revealed clear, regular fluctuations

Klyashtorin et al (“Cyclic
changes of climate and major commercial stocks of the Barents Sea”,
Marine Biology Research, Vol.5, 2009 [http://www.informaworld.com/smpp/content~db=all~content=a907041648#]):
“Spectral analysis of
100-year time series of Arctic surface temperature (Arctic dT), mean temperature of 200-m water column along the Kola
meridian and global surface temperature anomaly (Global dT)
was performed. It is shown that climatic indices of the Arctic region undergo
long-term 50-70-year fluctuations similar to fluctuations of Global dT and Arctic dT for the last
1500-year reconstructed period and the recent 140 years of instrumental
measurements. Long-term changes of Atlantic spring-spawning herring and
Northeast Arctic cod commercial stocks also show 50-70-year fluctuations that
are synchronous with the fluctuations of climatic indices.”

ThermoHaline Circulation (THC)

William Gray, the foremost hurricane expert and Professor
of Atmospheric Science at Colorado State University published the following
figure showing a 60-year cycle in the North Atlantic thermohaline
circulation (W. M. Gray, 2009: Climate
change: Driven by the ocean – not humans. The Steamboat Institute Conference, Steamboat Springs, Colorado, August
29, 2009. [http://tropical.atmos.colostate.edu/Includes/Documents/Presentations/graysteamboat2009.ppt])

This may be related also to the AMO.

El Nino

The
following figure shows “21-year
sliding window correlation between Nino3AM and CPI AM (thick solid line), and
between Jan-Feb TA cross-equatorial SSTA gradient and CPI AM (thin solid
line). The sign of the first correlation is reversed. The dashed line is the
5% (2 sided) significance level based on the Student's t distribution (N-2
degrees of freedom) for the null hypothesis of no association. Bars are the
number of Nino3AM events above 28oC in a 21 year sliding window (y axis
values to the right).” [http://shadow.eas.gatech.edu/~kcobb/seminar/chiang00.pdf]
Nino3AM is the Nino 3 region index April-May and CPI is a precipitation index
related to Brazil rainfall. The correlation between these two (thick line)
shows a 60 year cycle, as does the number of Nino 3 AM events above 28
degrees in a 21-year sliding window (vertical bars).

I was reading Ronald Wright’s
book “Time among the Maya”, published in 1989. Wright arrived in Flores
on the island in Lake Peten Itza and the proprietor
told him about the fluctuating lake level: “Look
at those poor fools! People come here and they don’t listen to the older
folk. We Peteneros – we know the lake has a cycle
every fifty years or so.”

The Hillesheim
et al paper “Climate change in lowland Central America during the late deglacial and early Holocene” (Journal of Quaternary
Science, 2005 [http://snre.ufl.edu/graduate/files/publicationsbyalumni/Hillesheim,%20Buck%20et%20al%202005.pdf]):
“the observed changes in
lowland Neotropical precipitation were related to
the intensity of the annual cycle and associated displacements in the mean
latitudinal position of the Intertropical
Convergence Zone … Lake Pete´n Itza´ is a terminal
basin fed by precipitation, subsurface groundwater inflow, and a small input
stream in the southeast. The basin is effectively closed, lacking any surface
outlets, although some downward leakage may occur. Lake Pete´n
Itza´ is situated in a climatically sensitive region where the amount of
rainfall is related to the seasonal migration of the Intertropical
Convergence Zone (ITCZ) and Azores–Bermuda high-pressure System. Lake Pete´nItza´’s volume is
sensitive to precipitation changes and has fluctuated markedly in the recent
past. For example, mean annual rainfall during the period from 1934 to
1942 was relatively high (2055mm/yr) and resulted
in increased lake levels and flooding (Deevey et
al., 1980). In contrast, the early to mid-1970s were relatively dry (mean
annual rainfall 1415mm/yr) resulting in lower lake
levels. During the late 1970s lake level rose again in response to increased
precipitation continuing until the early 1990s at which time the trend
reversed.” This is an approximately 60-year cycle.

This is implied by Knudsen et al (“Tracking the
Atlantic Multidecadal Oscillation through the last
8,000 years”, Nature Communications, 2011, [http://www.nature.com/ncomms/journal/v2/n2/full/ncomms1186.html]):
“these
sites [in central America] seem to have become more sensitive to changes in
ITCZ, and hence the AMO, as even slight changes in North Atlantic SST can
cause N-S shifts in the ITCZ and thus in rainfall.” Since the
AMO is on a 60-year cycle, the ITCZ also varies on a similar cycle.

The following figure is from
Figure 5 in Knudsen et al showing the spectrogram highlighting the 58-61 year
periodicity in the Lake Chichancanab data in the
Yucatan.

In this figure, the blue shaded
bands show the result of 19 simulations from 5 climate models using only the
natural forcings. Red shaded bands show the result
of 58 simulations from 14 climate models including anthropogenic CO2.

The following figure (right)
shows the Hadley / Met Office data shown at the start of this document,
superimposed on the models. (The zero location is different since the model
plot is based on a 1901-1950 average whereas the Hadley plot is based on a
1961-1990 average.)

The above figures show the following:

Prior to about 1970,
the global warming is fully explained by climate models using only natural
forcings (i.e. no human CO2 / GHG)

The models cannot
explain the warming in the 1930s

The sixty-year cycle
is completely absent from the models

The following figure compares the two recent 60-year
cycles (shown previously near the start of this document). There appears to
be a serious problem with the models when two identical cycles have two very
different stated causes – one natural, the other CO2-induced.

If the climate models cannot reproduce the 60-year
cycle that is evident in many climate phenomena, there is clearly a
fundamental problem with the models.

Solar System Influence

Nicola Scafetta has identified
the change in the location of the center of mass of the solar system (CMSS)
as a possible mechanism driving the 60-year cycle. (Scafetta,
N., “Empirical evidence for a celestial origin of the climate oscillations
and its implications”, Journal of Atmospheric and Solar-Terrestrial
Physics (2010), doi:10.1016/j.jastp.2010.04.015 [http://arxiv.org/PS_cache/arxiv/pdf/1005/1005.4639v1.pdf])

Scafetta shows the following figures described as: “[A- (left)] Rescaled SCMSS 60
year cycle (black curve) against the global surface temperature record (grey)
detrended of its quadratic fit; [B- (right)] Eight
year moving average of the global temperature detrended
of its quadratic fit and plotted against itself shifted by 61.5 years. Note
the perfect correspondence between the 1880-1940 and 1940-2000 periods. Also
a smaller cycle, whose peaks are indicated by the letter “Y”, is clearly
visible in the two records. This smaller cycle is mostly related to the
30-year modulation of the temperature. These results reveal the natural
origin of a large 60-year modulation in the temperature records.”
(SCMSS – Speed of the CMSS)

(Note: The term “barycenter” refers to the center of gravity
of a system, which would be the same as the center of mass in a uniform
gravitational field, and thus the two terms are often interchanged.)

As the planets orbit around the sun, the sun’s position
also changes as the whole solar system orbits around the CMSS, whose position
changes as the relative positions of the planets change. The planets / sun
influence this based on their relative mass. The following figure (left) show
a gravity simulation of the solar system barycenter position. The center figure
shows the hypothetical barycenter movement with Jupiter removed from the
system showing that Jupiter causes most of the wobble. The right-hand figure
then removes Saturn. Once Neptune is removed the effect of the remaining
planets is barely noticeable (not shown below). [http://www.orbitsimulator.com/gravity/articles/ssbarycenter.html]

Jupiter has the largest mass of any planet and thus is the
most influential. The Wolf cycle (solar sunspot cycle) has a period that
fluctuates but averages 11.2 years. Jupiter’s solar orbital cycle is 11.9
Earth years. Saturn, the second-largest planet, has a solar orbital cycle of
29.4 Earth years. This leads to Jupiter-Saturn conjunction every 19.9 years
(J/S Synodic Cycle). (As a coincidence, in the Maya calendar 1 Katun = 19.7 years.) A full cycle of Jupiter / Saturn
around the sun (J/S Tri-Synodic Cycle) is 59.6 years – in other words it
takes 60 (59.6) years for the Earth / Jupiter / Saturn reach the same
relative alignment around the sun.

The following figure shows the speed of the Sun relative
to the CMSS showing “20
and 60 year oscillations”. (From the Scafetta
paper referenced above.) It shows a 60-year cycle with peaks similar to the
global average temperatures shown at the start of this document – around
1880, 1940 and 2000.

“Herein
we show that the historical records of mid-latitude auroras from 1700 to 1966
present oscillations with periods of about 9, 10–11, 20–21, 30 and 60 years.
The same frequencies are found in proxy and instrumental global surface
temperature records since 1650 and 1850, respectively, and in several
planetary and solar records. We argue that the aurora records reveal a
physical link between climate change and astronomical oscillations. Likely in
addition to a Soli-Lunar tidal effect, there exists a planetary modulation of
the heliosphere, of the cosmic ray flux reaching
the Earth and/or of the electric properties of the ionosphere. The latter, in
turn, has the potentiality of modulating the global cloud cover that
ultimately drives the climate oscillations through albedo oscillations. In
particular, a quasi-60-year large cycle is quite evident since 1650 in all
climate and astronomical records herein studied, which also include a
historical record of meteorite fall in China from 619 to 1943. These findings
support the thesis that climate oscillations have an astronomical origin. We
show that a harmonic constituent model based on the major astronomical
frequencies revealed in the aurora records and deduced from the natural
gravitational oscillations of the solar system is able to forecast with a
reasonable accuracy the decadal and multidecadal temperature
oscillations from 1950 to 2010 using the temperature data before 1950, and
vice versa. The existence of a natural 60-year cyclical modulation of the
global surface temperature induced by astronomical mechanisms, by alone, would imply that at least 60–70% of the warming
observed since 1970 has been naturally induced. Moreover, the climate may
stay approximately stable during the next decades because the 60-year cycle
has entered in its cooling phase.”

“The
most prominent cycles that can be detected in the global surface temperature
records have periods of about 9.1 year, 10-11 years, about 20 year and about
60 years. The 9.1 year cycle appears to be linked to a Soli/Lunar tidal
cycles, as I also show in the paper, while the other three cycles appear to
be solar/planetary cycles ultimately related to the orbits of Jupiter and
Saturn.” The following figure from that paper show the prominence of
the 60 year cycle.